The show had a lot of things going on behind the scenes that caused some of the uneven nature of the series. I also recall it aired on Saturday nights most of the time, which didn't help.
In the hands of a better set of writers, the show could have been an interesting dramedy-type show rather than the slapstick/insult comedy that it became. The main thing I recall from watching the show is that they over-used the laugh track. Nell agreed to become live-in housekeeper for Chief Kamisky after his wife (Nell's best friend) died, putting aside her own dreams of being a singer. To say the Chief was overwhelmed would be an understatement, given his innate gruff nature and inability to provide a "soft touch" when needed. Dolph Sweet could have easily played a more three-dimensional father struggling to raise his kids alone and confiding his insecurities to Nell....but the show chose instead to make the family dynamic more of "Nell and the girls try to get The Chief to lighten up" or "Nell and The Chief have another argument over ____" Yes, Nell Carter was the star of the show, but they took too many liberties in the idea that Nell was better for the girls than their father was, like he was some villain they had to battle together. Her insult humor landed mostly on The Chief, though he returned fire quite well. And just when that dynamic was established....Dolph Sweet died, forcing the show to shift its focus once again. The writers' burden was actually lightened, since Nell could now function as 'mother' to the girls (and yes, to little Joey Lawrence) without having to battle The Chief over the proper decisions. But without someone to bounce the insults off of, Nell was a bit lost. They brought in Telma Hopkins as Nell's friend Addie, since she had to have some adult interaction and a new character to insult and be insulted by. The whole situation of these girls losing both their parents and Nell taking on the role of mother AND father to these girls (and later Joey, the orphan...? I think that's how he ended up in the mix) could have brought out a lot more character-based drama and not just the slapstick. When the eldest daughter got too old for the "coming-of-age" stories, they phased her out, and they married off the middle daughter I think....they had Nell, Joey and the youngest daughter (and Addie, I think) move to New York to give the show a soft reboot. When a show packs its characters up and move them across the country like that, it's usually a signal they've run out of ideas.
When this show premiered, NBC was in bad shape creatively, so I can imagine a situation where they enthusiastically signed "Broadway star Nell Carter," deciding to hire the talent, and then only developing the project afterwards. The premise was sound, but the characters and the settings needed more development rather than just hitting the air as it did. For several years afterward NBC had a terrible track record with its new shows, so they likely decided to keep giving them a break (so to speak) and renewing the show because they had so few successful shows to brag about. It wasn't until 1987 or so that they had enough hit shows to fill up the schedule that they could afford to ditch some of the dead wood.
